1. Field of the Invention
This invention relates to the field of semiconductor substrate manufacture; i.e., a substrate on which semiconductor materials or devices can be formed.
2. Description of the Related Art
The present invention makes use of a separation by implantation of oxygen (SIMOX) process.
In accordance with this invention, a SIMOX process provides that oxygen implanter apparatus is used to create a very thin silicon dioxide (SiO2, SiOx) layer that is buried within a relatively thick silicon carbide (SiC) wafer, thereby leaving a thin membrane layer of SiC on top of the SiC wafer. For example, such oxygen implantation equipment is manufactured by Ibis Technology Corporation.
The present invention uses a step of etching SiO2 (SiOx) in hydrofluoric acid.
The present invention uses a wafer-bonding step. Wafer bonding of a variety of materials is known.
U.S. Pat. No. 5,798,293, incorporated herein by reference, is cited for its teaching of the production of a semiconductor layer of SiC of the 3C polytype on top of a semiconductor substrate layer using a wafer-bonding technique.
U.S. Pat. No. 5,877,070, incorporated herein by reference, is cited for its teaching of transferring an upper portion of a first mono-crystalline substrate to a second substrate using hydrogen trap-induced implantation of the first substrate, forming micro-cracks in the hydrogen traps, direct wafer bonding the first substrate to the second substrate, and growing the micro-cracks such that the upper portion of the first substrate separates from the first substrate.
U.S. Pat. No. 5,966,620, incorporated herein by reference, is cited for its teaching of the use of the implantation of helium ions or hydrogen ions into a single crystal silicon substrate in order to form micro-cavities in the implantation region. Separation is achieved due to the fragility of the implantation region, and by the application of an external force, by oxidation of the implantation layer, or by laser heating of the implantation layer.
U.S. Pat. No. 6,054,370, incorporated herein by reference, is cited for its teaching of the formation of first damaged regions in a substrate underneath areas wherein active devices are formed forming second damaged areas in the substrate at locations between the first damaged regions, causing a film to detach from the substrate at locations where the first and second damaged regions are formed, and transferring the film to a wafer.
U.S. Pat. No. 6,120,597, incorporated herein by reference, is cited for its teaching of the detaching of a single crystal film from an epilayer/substrate or bulk crystal structure wherein ions are implanted into the crystal structure to form a damaged layer within the crystal structure at an implantation depth below a top surface of the crystal structure, and wherein chemical etching effects detachment of the single crystal film from the crystal structure.